Retrospective comparison of treatments for equine gastric ulceration syndrome and the influence of inflammatory bowel disease

Summary Background Equine squamous gastric disease (ESGD) and equine glandular gastric disease (EGGD) can be treated with oral omeprazole, combined with sucralfate or an extended‐release intramuscular omeprazole (ERIO). Objectives To evaluate these different treatments for ESGD and EGGD and assess the influence of inflammatory bowel disease (IBD) on treatment response. Study design Retrospective analysis of gastroscopic images and patient records of horses diagnosed with ESGD and/or EGGD at Utrecht University between 2017 and 2022. Methods Outcomes following oral omeprazole (OROM), oral omeprazole combined with sucralfate (OROMSUC) and ERIO were compared. Extended‐release intramuscular omeprazole was administered only to horses that had failed to respond sufficiently to oral therapy. The impact of concurrent IBD on treatment response was assessed. Results Fifty‐nine horses received OROM, 68 OROMSUC and 19 ERIO. All treatments improved ESGD scores ( p < 0.001) with no difference between treatments. For EGGD, OROM showed no improvement ( p = 0.3), whereas OROMSUC ( p < 0.001) and ERIO ( p = 0.02) did. Compared to OROM, both OROMSUC ( p < 0.0001) and ERIO (0.02) resulted in greater reduction of EGGD scores. In 50% of horses in the OROM group, EGGD scores increased after treatment ( p < 0.0001). Horses with untreated IBD were 3.4 (95% CI: 1.7–6.8; p = 0.004), times less likely to show improvement in EGGD scores than horses without IBD, a similar effect was observed for ESGD with an OR of 2.1 (95% CI: 1.1–4.1, p = 0.03). Main limitations Nonrandomised treatment allocation due to the retrospective design. Conclusion Oral omeprazole monotherapy cannot be recommended for EGGD. The efficacy of ERIO in this study, where it was exclusively used if oral treatment had failed, was lower than previously reported. The presence of untreated IBD negatively affected treatment success for both ESGD and EGGD.